1. Field of the Invention
The present invention relates generally to image transistors for amplifying light signals. More particularly, the present invention relates to a laminar flow water cooling system for an image transistor, which allows the use of higher power light sources without overheating the materials of the image transistor.
2. Related Art
A variety of devices and schemes have been developed for amplifying light signals or images. One of these is known as an image transistor, also called a light valve. These have been known for some time. Image transistors amplify light signals using a liquid crystal modulator to transfer the characteristics of a low power image to a higher power light signal. An image transistor takes an image cast upon its rear surface and uses the photon energy of that image to alter the state of liquid crystal material. The liquid crystal material in turn transfers the characteristics of the image to light energy which is cast upon the front surface of the image transistor. Thus, any light cast upon the front surface of an image transistor is reflected back as the image cast upon the rear surface. Accordingly, image transistors allow amplification and higher power transmission of low power light signals and images, and are very useful for a variety of display devices.
However, liquid crystal material has a very limited operating temperature range. When subjected to intense light, the liquid crystal modulator of an image transistor will overheat and cease to function. Consequently, image transistors have heretofore only been used with low power light sources, and not with lasers or arc lights. This limits their utility and flexibility. If an image transistor could be used with higher power light sources, they could be used for projecting larger images, or projecting them over larger distances, or with greater intensity. There are numerous possible applications for high power image transistors.
It has been recognized that it would be advantageous to develop an image transistor which can utilize a high power light source without overheating.
In accordance with one embodiment thereof, the invention advantageously provides a light transistor system, including an image transistor, and a coolant passageway, extending through the image transistor. The image transistor has a liquid crystal modulator, configured to amplify a low-power light signal using amplification energy from a higher-power light source, such as a laser or arc lamp. The coolant passageway is configured to receive a flow of coolant therethrough, to allow cooling of the image transistor to prevent damage to it from the higher-power light source.
In accordance with a more detailed aspect of the present invention, the system includes a radiator disposed in a loop in fluid communication with the coolant passageway, configured such that thermal energy is removed from the coolant as it circulates by convection through the image transistor and the radiator.
In accordance with another more detailed aspect of the present invention, the system includes a radiator and pump disposed in a loop in fluid communication with the coolant passageway, configured to circulate the coolant through the image transistor and remove thermal energy therefrom.
Additional features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention.